Heating, ventilation and air conditioning can be broken down into two types of systems, that is, a self contained system and a non-self container system. A self contained system is limited to a specific area, has its own manufactured purchase package components (blower, coil, duct work, inlet, outlet, etc.), and is independent from other sources. Some examples are window air conditioners, unit heaters, wall heaters, roof top package units, room fan powered package units, rest room ventilators, air curtain door fans, etc. A non-self contained system has a central primary air source (air handler or furnace with blower), serves a whole structure or building, is not limited to a specific area, and is made up of various manufactured components.
Most modern heating and/or air conditioning systems used in the world today are non-self contained systems and employ forced air circulation, that is, air is drawn from a room to be heated or cooled, passed through a heating and/or air conditioning system in which the air is heated or cooled and then distributed back through a duct work system to the room to thereby raise or lower the air temperature in the room according to comfort requirements. In some instances air is merely circulated in such system without heating or cooling to improve ventilation. While the air distribution system can be arranged to discharge forced air through the floor, or through a wall of a room, the most common practice is to discharge air, whether for heating, cooling or for ventilation, through the ceiling. A primary reason that discharge of air is made through the ceiling rather than through a floor or wall vent is that most building construction permits ready access to a ceiling compared to a floor or wall.
To distribute air from a forced air system through a ceiling the common practice is to utilize a ceiling vent which typically is designed to not only provide an opening through which air can pass through a ceiling into a room but also to aid in distribution of air in the room. A third desired aspect of a ceiling vent is to provide improved appearance, that is, to provide a way for air to enter a room that is other than simply a hole in the ceiling with which a forced air duct communicates. A covering placed in or over a hole in a ceiling that communicates with a forced air duct is referred to as a "diffuser" or sometimes as an "air register".
Almost since the availability of electrical energy, a way to improve the comfort of a room has been by use of a ceiling fan. Ceiling fans are employed throughout the world and typically consist of a motor having a vertical shaft attached to a hub from which a plurality of blades radially extend. The typical ceiling fan has relatively large blades and the fan is designed to turn the blades at a relatively low rpm so as to achieve good distribution of air in a room without producing excessive noise as is common with a fan that utilizes a small diameter blade rotated at a high rpm.
Ceiling fans are mounted so that the motor is in close proximity to the ceiling with a downwardly extending shaft to which a hub is attached at the lower end. Other ceiling fans employ motors wherein the rotor itself functions also as the hub with blade attachments secured directly to the rotor. Such fans are typically mounted so that the motor is spaced from the ceiling.
Ceiling fans are popular because they have relatively low energy requirements, are effective in air distribution and are quiet. When a room is supplied with an air diffuser for distributing forced air into a room along with a ceiling fan plus the typical light fixtures, a ceiling of a room can become very "busy", that is, cluttered with a number of different items that detract from the appearance of the ceiling. Further, when a ceiling fan is used in a room that also has an air diffuser, and where the air diffuser of the ceiling fan are spaced apart from each other, equal distribution of the forced air from the diffuser is not always effectively achieved.
It is an object of this invention to provide a combination air diffuser and ceiling fan to achieve two basic functions. First, by combining an air diffuser and ceiling fan appearance is enhanced by the decreased number of separate components attached to or extending from the ceiling. Second, and of greater importance, by combining an air diffuser and ceiling fan the effectiveness of distribution of forced air into a room is enhanced.
Others have provided improved means of air distribution combined with ceiling fans and the following previously issued United States patents provide good background information relating to the subject matter of the present invention.
______________________________________ U.S. PAT. NO. INVENTOR TITLE ______________________________________ Re. 33,347 Johnson III Air-Driven Ceiling Fan 571,424 Wolfe Heating and Ventilating Apparatus For Buildings 1,333,651 Andrassy Ventilator 2,038,347 Cornell, Jr. Air Conditioned Heating and Cooling System 2,093,936 Spielmann Air Conditioning Device 2,239,848 Jackson Air Conditioning Apparatus 2,363,839 Demuth Unit Type Air Conditioning Register 3,760,708 Burup Ventilating System 4,191,506 Packham Propeller and Impeller Constructions 4,326,453 LaBoda et al Air Transfer Device 4,598,632 Johnson III Air-Driven Ceiling Fan 4,779,671 Dolison Cooling, Heating and Ventilation System 4,782,213 Teal Ceiling Fan Electrically Heating Environmental Air 5,029,451 Imaiida et al Air Conditioning Apparatus 5,097,674 Imaiida et al Air Conditioning Apparatus 5,462,407 Calvo Ceiling Fan Blade and Hub Assembly ______________________________________